ios 导航栏回退和分栏切换同时进行时，导航回退不执行解决方法

1.异步执行导航栏控制器回退回跟页面，以下vc为当前控制器

dispatch_async(dispatch_get_main_queue(), ^{

        [vc.navigationController popToRootViewControllerAnimated:NO];

    });

2.分栏切换显示页

AppDelegate *delegate = (AppDelegate *)[UIApplication sharedApplication].delegate；

UITabBarController *tabbarCtr = (UITabBarController *)delegate.window.rootViewController;

[tabbarCtr setSelectedIndex:index];